In recent years, a transparent organic polymer material has been used as a transparent material to replace inorganic glass. In the case where such a material is used in, for example, optical applications such as spectacle lenses, it is required to have a high refractive index while having generally required properties such as transparency, thermal properties, and mechanical properties.
As a related art relating to such a resin, Patent Document 1 describes examples of using a compound having a disulfide bond. Further, Non-Patent Document 1 describes that a resin is obtained by copolymerizing a compound having sulfur atom and a triple bond with a polythiol, although optical properties of such a resin are not known.
Further, as a related art relating to a resin, there is a disclosure of Patent Document 2. The same document describes a metal-containing thietane compound. Further, a high refractive index optical material having a refractive index (nd) of more than 1.7 is described therein. Further, there is a description in Patent Document 3 that a high refractive index optical material having a refractive index (ne) of more than 1.8 is obtained by using an antimony thietane compound. Further, Patent Document 4 describes that an optical material having a refractive index of 1.643 is obtained by using an antimony arylthiolate compound. Patent Document 5 describes that an optical material having a refractive index of 1.730 is obtained from a polymerizable composition containing a propargyl isocyanate and a polythiol compound.
In addition, Patent Document 6, and Non-Patent Documents 2 to 5 disclose compounds having triple bonds at both terminals thereof.